S.C. Code Ann. § 58-17-1670
The Commission may examine all agents and employees of such railroad companies and other persons under oath and otherwise, in order to procure the necessary information to make just and reasonable rates of freight and passenger tariffs, and to ascertain if such rules and regulations are observed or violated and to make necessary and proper rules and regulations concerning such examinations. Such rules and regulations herein provided for shall be obeyed and enforced as all other rules and regulations provided for in this chapter.